Lifting jack



June 30, 1925.v

E. W. HOLMES LIFTING JACK 4 sheets-sheet 1 Filed Sept. 273, 1924 June E, i925.

E. W. HOLMES LIFTING JACK' Filed Sept. 2 3, 1924 4 Sheets-Sheet 2 June E@ E. VV. HOLMES LIFTING JACK Filed Sept. 25, 1924 57 y' 2% y o 1J @Hoznuu June B, 1925.

E W. HOLMES LIFT ING JACK (CJ uve u to@ E' H1657* W Holmes,

Datented t.lune 3Q, 1925.,

ERNEST 'W'. HOLMES, 0F CATTANOOGA,

STATES istante TENNESSEE. ASSXGNOR TO ERNEST' HOLMES LFTING JACK.

Application ed September 23, 1924. Serial No, 739,380.

To all whom it may concern:

Be it known that I, ERNEST W. Homme, a citizen of the United States, residing at Chattanooga, in the county of Hamilton and State of Tennessee, have invented new and useful Improvements in Lifting Jacks, of which the following is a specification.

This invention relates to lifting jacks for automobiles and proposes the construction of a jack characterized by simplicity of operation and efficiency in action.

The principal object of the invention is the provision otmeans for enabling the jack automatically to performr its reverse or loadiowering function :tor any of various lengths of stroke ot the jack handle, through a single manipulative movement of the hand, by the wielder of the jack handle, the position ot' the hand acquired by said movement being maintained throughout t-he load-lowerinooperation. Y

rl`his is in contra-distinction to the usual mode of operationof variable-stroke jacks, in which a milking action of the hands must be resorted to at the end of each stroke to reverse the positions of the lifting and holding pawls.

Other objects of the. invention will be disclosed as the description of the illustrative embodiment of the invention develops.

.in the drawings:

Figures 1a, 1b and 1c representa side elevation of my iniproved jack, partly in section.

Figures 2, 2"' and 2*2 represent a plan view oi' the jack also partly in section.

Figure tl is a side elevation of the revers-v ing cam, several positions of the setting mechanism being indicated.

Figure 4 is a seetion taken l-4 of ll`igure 1b." :i

Figure 5 is a transverse section taken along the line .ST5 of Figure 1,

Figure' 6 is a side elevation of the jack showing the handle in folded position and indicating another position of the handle in dotted lines.

Referring now in detail to the several tigures, the numeral 1 represents the main i'rame of the jack, said frame preferably consisiing of an integral bent member having the side members 2 and the end portion 3.

along the line The side members 2 extend forwardly to the point indicated at 4 in Figure 2b. The main frame is supported upon the vehicle Wheels 5 and 6, the latter being' carried upon an axle i which passes through suitable apertures in the side members 2 adjacent the end member, the axle being rigidly clamped against said end member` by means of a U- bolt 8 which passes around-said axle and through suitable apertures .in said end member. -rlhe vehicle wheels pleiterably rotate upon roller bearings 9. rlfhe side members 2 of the` main iranio are bridged adjacent their ,forward ends by nicans of the brace plate 10, zthe latter being 'flanged at the sides as shown at ll. the bolted or otherwise rigidly secured to said side members. The brace plate itl is preferably formed ou its under face with a cylindrical boss l2. said boss fitting within a cup 13, the latter constituting part of the caster 14k and being pivotally secured to said brace plate centrally of the boss 12 by means ot' the pin 15. The boss 12 and cup 13 together form a race-way in which the antifriction rollers 1G are retained. The vehicle wheels 5 and G being independently mounted upon the axle have a ditl'erential .movement so that the jack may be freely rotated about a vertical anis passing` through some point in the axle, the caster 14 arranging itself` so that its plane of rotation lies perpendicular to the radiuspf rotation of the jack.

The forward ends of the side members 2 are perforated for the reception of 4a pin 17 upon which the portions of the jack mechanism presently to be described are mounted and which affords pivotal connection for the jack handle or lever 18. A spring 39 surrounds the pin 17 and engages the main frame and the jack handle, the function of said spring being to normally maintain the jack handle in an anuglar position approaching the vertical, said posit-ion being'indicated -by dotted lines in Figure 1l. T he jack handle comprises the side members 19 shown in Figure 1 which are preferably brought together as shown at 20 where they are connected to the transverse handle bar 21. The main lifting member of the jack, which will hereinafter be ilanged portions beingreferred to as the canti-lever, consists of a substantially U-shaped member 22 lyingthe side members of said main frame at an intermediate point. A spacing sleeve 2'4 may be provided, surrounding the middle portion of said pin and keeping the legs of said cantilever separated and in close proximit-y to the side members of the main frame. j

The cantilever is raised; 'by a wedge 25 which re-acts upon bearings carried by said main frame and canti-lever, `between which said wedge is adapted to pass. These bearings are carried at points on said canti-lever and main frame intermediate the outer ends ofsaid members and their pivotal connco# tion. In order to avoid weakeningthe side members of the main frame lby undue perforations, saidr side members are fitted with saddle plates which preferably consist of .spaced side walls joined by a top wall, forming a deep channel through which the side frame members extend. Said' saddle plates may be of any convenient shape but are here shown as triangular and riveted to the main frame at points 27 and 28 adjacent two of the vertices thereof. The saddle plates extend below the side members of the main frame and are perforated to receive the roller lhearings 2f). A shaft 30 passes through said bearings, upon which is mounted the roller 3l, said rolleryybeing of sufficient length to occupy substantially the full width of space between said side mem bers, affording lateral support to said side members. ',lhe .canti-lover 22 is provided above said bearings with a similar set of roller bearings 32 in. which is journalled a shaft 33 carrying the roller l34. The latter roller is of suiicient width to fit between the legs of the canti-lever. The wedge 25 rests upon the roller 3l and raises the roller 34,

and with it the canti-lever. Said wedge is of trapezoidal cross section, the bottom face thereof being as wide as the lower roller and the top face being equal in width to that of the upper roller. The rearward on broad end of the wedge is curved upwardly at the bottom so that it will ride over any uneven places in the garage floor, when the jack is moved in a backward direction., The nose or apex of the wedge is secured in any suitable manner to a rod 35 which passes 4fo: ",.vardly over the pin 23 and the spacing sleeve 24 and is connected at its forward end 36 to a flexible section or chain 37k the latter being secured at its opposite endto a ratchet drum 38, best shown in Figures l and 2b.

The'ratchet drinn 38 is preferably freely mounted .upon the pin li and isprovided on one side with a iange or lug 40 and on the other with a ratchet wheel 4l. "A pin ing pawl 43 .which co-acts with the abrupt shoulders of the ratchet teeth 44'on the downward stroke of the'jack handle, and rides vover the slopingr faces of said ratchet teeth upon the upward stroke of the jack handle. The ratchet wheel 41 is retained in any position by means' of the holding pawl Lifting and holding pawls for a ratchet wheel in jack construction are well known but the present lifting and holding pawls, and the controls therefor are of novel and peculiar construction as will presently There is nothing notable in the manipulation ofthe jack handle in performing the liftingoperation. The jack handle is forcibly depressed, the lifting pawl carrying the ratchet wheel around for a certain fraction of a revolution, the load boing transferred to the holding pawl and the latte ,preventing reverse-movement of the ratciet Wheel when the handle is raised preparatory to the performance of another lifting stroke.

.That which is new, and which constitutes the amost important feature of the present invention `is the novel means called into operation for the performance' of the load lowering function of the jack.

Jacks of la type having a definite `length of stroke vhave long been known, in which means is provided for reversing the position of the pawls when changing from the lifting to the lowering function of the jack. But the trend of inventive effort in the evolution of recent jacks has been to devise a' vjack having available a number of lengths of stroke which may' be undertaken in various positions of the jack handle so as toV meet the numerous requirements and exigen# cies incident to modern garage service. In jacks of this type the problem has presented itself of constructing practical means for reversing the pawls to perform the lowering operation for any one of the various lengths of stroke. Up to the present time such means Ahave been exemplified by separate devices onor adjacent to the handle of the jack for independently releasing the'pawls,

which, devices must' be separately manipulated at the end of each stroke in a manner which canbe learned only by much practice and which is referred to in garage parlance as milking the jack. The-present vinvention seeks to simplify the reversing means tor iaeks o t the variable stroke type through the operation ot' instrumentalities of which the following are an example.

7fha lifting pawl 13 forms partot a east-I ing which includes the sleeve 4G mounted upon the transverse member 47, the latter lying between the side members 19 of the jurk handle and being provided with trunnionsv lh, rotating within bearings in Said side members. rl`he bore within the sleeve lll extends radially with respeet to the axis of rotation of the member L17. The casting is also formed with an arm 49 terminating in an eye 50. .A U-bolt 51 has one limb 52 reeiproeably mounted within the` sleeve 46 and the other limb 53 projecting through the eye l). An operating` rod 54 engages the bend ol the U-bolt. said operating rod being connected to a bell-erank lever 55, best shown in Figure 2, the free end 56 of which extends to a position adjacent one side ot the handle bar 2l. their the end 56 of the bell-erank lever is pushed inwardly longitudinal movement is transmitted to the lJ-bolt 5l through the rod 54. A spring 57 eneireles the limb 53 ot' the U-bolt and is retained 'under compression between tbeleye 50 and the operating rod 54. By means of this spring the Uebolt remains normally relrarted. The lifting pawl l3 is norn'ially biased toward said rateliet wheel. by the torre ot' gravity acting through the. weight 5H. rarried by an arm 59. and preferably l'ori'ningg' part of the 'asting The U-bolt is out ot the plane of the lifting pawl and ratrhet wheel, and the limb 52 ot said U-bolt ll l) lies in the plane ot the eam (30.

Said 'am is liournalled upon the pin 17. The (fam is termed. on that portion which is designed to ro-art with the limb 52 ot the lj-bo'lt, with shoulders of various heigl'its having lsubstantially radial walls. The shoulder Gl is the most elevated, Shoulders n2 and (lil are ol substantially the same height. while shoulder (il is the lowest, The number ol' shouhlers is immaterial,y and other shoulders than those shown may be provided without in any way transii'ending the seope oll the invention. The shoulders define belweeu them spares into which the limb 52 ol the U-bolt may deseendanzl within whieh it may have ranges ol movement ot various lengths. the object ot said spaces being to eause partial rotation of the ram (l0 in a manner that will presently be described. tor various lengths otJ stroke of the jack handle determined by the space available for movement ot the liaek handle.

lhe holding pawl 45 is preferably formed integral with a easting (l5 which is pivot-ally mounted upon thepni (5G. Said casting is provided, at one side ot the holding pawl and in the plane ot' the eam 60, with a pair of keepers (i7 and 68 lying on opposite sides ol the axis of the pin m66. The cam is prostrikes vided on that side opposite the series of shoulders above mentioned, with a tubular extension 69, within which a plunger 74D slides. said plunger being normally urged outward by means of a spiral spring 71 within said tubular extension. The plunger normally rests within the keeper G8 but the cam is capable ot a degree ot rotation sailieient to Cause the plunger to ride over the side of the pin 66 and to `lodge in the other keeper 67. The pin G6 therefore serves as a detent to assist in retaining the plunger in one or the other ol' the keepers. In the normal position shown in Figure l" the plunger is in engagement with the keeper 68. the pressure of said plunger normally biasing the holding pawl into engagement with the ralehel wheel. .lt is obvious that when the Cani is turned so that the plunger ro-aets with the keeper GT the pawl is biased in the opposite direction, that is to say. away from the ralehet wheel.

'lhe rusting li and its aiipurlenanees inrluding the U-bolt 5l perform two functions.. namely 'setting the lifting pawl 53 alternately in operative or release positions. and throwing the cani titl into normal (lifting) or release (lowering) positions. ily way ot illustration, the operation ot the mechanism will now be traced beginning with the normal repose position ol the iaek handle shown in dotted lines in Figure l. This is the posit-ion whieh the jack handle. assumes` when let go,\under the tension o l the spring 3l). As the jack handle flies up to this position, the end ot vthe limb 52 ot' the U-boll the most elevated ot the veaux shoulders. (il, ensuring the'oseillation o'l' said (tam. if it is in reverse position. bark to normal position with the plunger TO engaging the keeper (i8. lt the ram is, already in normal position the shape ol the keeper is such as to prevent the plunger from esraping therefrom and no movement ol the earn lakes plat-e. ln either event the rusting lll) lli' is swung in a rounterrlmkwise dirertion so that the lifting pawl is raised lo the release position. 'lhe extent ole the rouuterrloekwise swing ot' the rusting 4T is limited by the arm 59 which is preferably bent so as to extend bark ot the jack handle. and to engage. the latter. the posilion ot engagement being elearly shown at 72 in Figure l. The 'advantage ot this construction is thatsbould the yiark handle aeeidentally slip from the hand ot' the .operator while a load is being li l'ted, said handle would automatieally and instantly fly up and swing the earn (l0 so as to plaee the holding pawl in a position to retain the load preventing the latter l'rom falling willi the jark. lVhen the parts are in the dotted line position shown in Figurel 1h. the jack handle may be folded down above the main 'trame as shown in Figure 6 after pushing the end 56 of the bell-crank lever outwardly a slight distance toward the end of the handle bar. This movement raises the lower end of the limb 52 of the U-bolt suiiciently to permit it to clear the end of the cam shoulder 61. The jack handle is provided adjacent its outer end with a projecting lug 7 3 adapted to rest in the middle of the lifting post which has not yet bien described, and on the opposite side of the jack handle is a similar protuberance 74 which strikes the ground when the ack handle is extended to the position shown in Figure 1, the purpose of which is to safeguard the operator from 'meshing his hand between the jack handle and floor when operating close to a horizontal position.

Referring again to the dotted lineposition of the jack handle, shown in Figure lb and supposing that the operator wishes to perform a lifting operation,he catches hold of the handle bar 21 with the full assurance that the holding pawl has been automatically vset for the lifting operation. In grasp ing the 'handle bar he avoids touching the end 56 of the` bell-crank lever. Vhen he first begins to pull down on the jack handle, the end of the limb 52. of the U-bolt disengages from the shoulder 61. This permits gravity, acting-through the weight 58 to swing the U-bolt in ay clockwise direction placing the lifting pawl 43 into engagement.

with the teeth 44 of the ratchet wheel. This disposition of parts is shown in full lines in Figure 1l. Thev operator depresses the jack handle through as great an arc as circumstances will permit, or a less arc if desired, the holding pawl 45 retaining whatever advance is made by the ratchet wheel. Nothing particularly novel happens on the up stroke of the jack handle, in the lifting operation, the U-bolt remaining swung over in a clockwise direction and the lifting pawl merely riding back over the sloping surfeces of the ratchet teeth.

y It will. now be supposed that the operator .wishes to lower the load. It is presumed "by way of illustration that the handle is in thenormal position of repose indicated by the` dotted lines in,V Figure 1b, but this will notf always be the case because automobiles var in. the amountof clearance beneath their axles, some being very low so that only a limited length of stroke is available. In such case the jack handle will be automatically lifted by the spring 39 to a position in which it collides with some part of the structure of the automobile which is being raised, and this Wilbe its position at the beginning of the l wering operation. In lowering the load the operator grasps the handle bar 21, pushes his iist against the end 56 of the bell-crank so as to depress the rod 54. This depresses the U-bolt 51 and compresses the spring 57. Compression of said spring places a thrust against the arm 49, biasing the casting 47 in a counterclockwise direction so that the lifting pawl 43 will remain in release position when the end of the limb 52 ofthe U-bolt disengages from the cam shoulder 61. This position is indicated in dottedV lines in Figure 3. The simultaneous depression of the end of the limb 52 places said end within one of the recesses formed between the shoulders upon the'arm 60, and the operator by moving the end 56 of the bell crank more or less in wardly toward the center of the handle bar determines which of the recesses said end shall enter. For instance, if he has available but a small range of mot-'ement for the jack handle whether the latter be in a sub` stantially vertical position as when working close to a wall or in a limited position near the horizontal as when working under a low hung axle, he pushes the end oi' the limb 52 of the U-bolt in as far las it will go. Should he be working with the jack handle near the vertical, the position ot the parts before de pression of the U-bolt will be that shown in dot-ted lines in Figure 1b. When the U-bolt is depressed the end of the limb 5f!- u' ill play within the recess between the cani shoulder 61 and the cani shoulder 62. Agt'ter having depressed the U-bolt into said recess the operator pushes down upon. the jack handle. This causes the vend of the limb to strike against the left hand side of the cam shoulder 62 as viewed from Figure l. Two results follow, one is the oscillation of the cam 60 in a clockwise direction throwing the plunger over into the keeper 67. This action is not suiiicient of itself to throw the holding pawl into inoperative position because the load is bearing down with great frictional pressure against the nose of the pawl 45, holding it in opposition to the releasing tendency of the plunger 70. The

other result is the swinging of the casting 47 in a clockwise direction against the tension of the spring 57. This throws the lifting pawl into operative position. As the opera tor bears down upon the jack handle, the' into operative position. As soon as the load.

has been taken upby the holding pawl the lifting pawl again flies outl under the pressure of the spring 57.

It will be understood that the operator maintains the `outer end 56 of thebell-crank 55 in depressed position during the entire rse/.rece y et load lowering movement of the jack and that he does not have to change the position of his hand during that movement.

If the jack handle can only he manipulated Within a narrow range of movementnear the horizontal, the end of the limb will play-within the deep recess between the cams 62 and G4, as shown in full lines in" Figure 3. G Should a greater range of movement of the jack handle he practicabley the operato-r will not have to Adepress the end of the ri-holt quite so far. lt may then operate between the cam shoulders GQ and 63, passing over the shoulder Should there he room for a full stroke of the jack the operator will press the Ueholt in hut a very slight distance so that the end of the lirnh will ytravel between the cam Shoulders 6l and 83.

define is purely illustrative and is not in-r tended to impose e limitation upon the invention.

The ratchet 'wheel il is limited in its movement in either direction hy means of a boss which projects from one side. of said ratchet wheel and migageahle with opposite sides ef the tubular extension of the cani 80. The ohject of this boss is to prevent excessive elevation of the canti-lever which might otl'iernise permit the Wedge Q7 to pass entirely through hetween the rollers 3l and 8&5 causing the load to crash. `When the extreme limit ascent of the cantilever heen reached the hoss 75 comes around and strikes the tubular extension on the under side1v throwing the cam GO to rever ion that further atteniptpto lift the load will result in the holding pawl dying out so that no fil er elevation of the cantilever' Willi sustained. Qonversely in der to prevent the cantidever being lowered too far Within the main frame the 1Doss 75 will strikel the upper end of 'the 'tubular exe tension while the fain 60 is in .reverse posi tion during the load lowering operation, throwing the plunf'er 7() over the normal position and causing the holding pawl to assume its operative iition, preventing further des ,nt of the lor-1d. Contact of the iriss'r with the tnli extension either at l )per or lower limit of the range of niovei'rieut of the lifing nier ianism resorts `pon the ratchet wheel. nhihiting its "further rotation and les in proper posiof the iii'tii'ig "i iis v he possiliility of I ronn Y an exc `v et ,in upon the lifting meelianism beyond the ratchet wheel incl: has reached its highest point., s the chain troni sap ing and he ground when the lifting mechrt point. The lower end sleusion 69 formed with relative thereto.A The lifting Post iS pro*v vided on its forward face With ratchet teeth 77 having the abrupt shoulders thereof downwardly directed and engagahle with a pawl 78 consisting preferably of a piece of strap iron having a fiat portion extending transversely of the canti-lever, and angularly lient portions extending downwardly at each side offthe cantidever and being pivoted thereto by means of the holt 79. An operating arm 8l) is secured in any suitahfe manner to one Side of the pawl 78 and is normally biased in an upward direction hy means of a spring 8l so that the transverse portion of the paivl 78 makes contact with the teeth carrying face of the lifting post. The bottom of the lifting post may he furnished with lugs 82 extending down wardly and engageahle with the lower edges of the canti-lever to limit the upward extension of the lifting post. A load supporting platform 83 is swivelly carried upon the top of the lifting post.

The object of the paivl 78 and ratchet teeth 771L is to enable the operator of the jack to maire a preliminary rough setting of the same at approximately the desired height to permit the jack to loe slipped under the load. 'llhishc does prior to the placing of the jack hy simply raising the platform 83 hy hand, the ratchet teeth slipping past the pawl 78. To loiver the lifting post the operator merely places his foot upon the operating bar 80, depressing the same against the tension of the spring 8l, this pulls the paw] 78 away from the ratchet teeth and the post drops. rPhe preliminary elevation of the post and its descent are always acco1nplished before placing the jack beneath the Work. 1

@ne ot the disadvantages attending the use of a wheeled 'jack is the ease with which. it slips about from under the Work While the jack handle is being manipulated in the lifting operation preparatory to the n'ionient when the jack Lahe-s hold of the work. This is avoided in the present invention by the use of auxiliary ratchet operating means consisting of an operating rod 84 having one end thereof conveniently adizufent the handie liar and the other end formed with a ratehetJA/hccl*tooth engaging portion 85. Said operating rod is normally biased away from the ratchet wheel loy means of the spiral spi-in;Y 8C arranged in compression he tween a collar 87 on the operatingrod and an eye 88 on the jack handle. Said eye surrounds the operating rod and has an aperture 89 of larger size than said operating rod so as -to provide lost motion in order to permit 'the operating rod to move downwardly relative to the handle of said jack i so as to follow the ratchet teeth around from the point at which it iirst makes contact with the ratchet wheel to the point of substantial tendency thereto. The auxiliary ratchet wheel operating mechanism is Worked up and down to rotate the ratchet Wheel in a canti-lever-raising direction. l

It will be understood that there are three distinct elevating means for the jack, first the lifting post which is directly elevated by hand, second the auxiliary ratchet wheel operatingmechanism which is operated while the jack is beneath the automobile the jack handle being firmly held, at the same time, to prevent the jack being displaced relative to the Work, and finally the main jack elevating mechanism which is operated by working the jack handle back and forth' in a well understood manner.

V Referring now to the jack as a whole, it will be noted from Figure 6 that the main frame l inclines downwardly from the end adjacent the caster 14 to the end adjacent the vehicle wheels, and that the canti-lever 22 is pivoted to the main frame at an intermediate oint. That portion of the cantilever adjacent its pivotal connection with the main frame slopes slightly upward, the result of this construction being that the lowest point on the entire jack is adjacent said pivotal connection. It is preferred to make the actual len h of the canti-lever, from the center of t e platform 83 to the pivot pin 23 equal to one-half the width of tread of an auto vehicle, that is to say 28 inches. This makes it possible to place the platform 83 beneath the middle of the front or rear axle by elevatin the axle just suiiiciently to permit the wheels to clean` the ground by a distance of equal to the ele-i vation of the low point of thejack, and to' swing the jack around to a position at right angles to its original position upon the axis of the platform 83 as a center beneath oneI of the elevated wheels of the auto vehicle. In this manner it is possible, with a mini mum amountof lifting to make almost any desired manoeuvre with the automobile in a limited space. It will be observed that the free end of the canti-lever inclines downward sufficiently to bring the platform 83 just below the level of the to i of the wheels 5 and 6 making it possible or the jack to be operated in any space through which the lvehicle wheels can pass. r

The chain 37 which winds around the ratchet wheel drum 38 is of novel construction, being designed to oppose as little frictional resistance as possible to the opera-4 the idea of making it materially easier to lift the load but to ensure the return of the wedge 25 by gravity to its normal inoperative position. The chain is constructed of pins 90 connected by side links 91.. Said side links are made larger at one end than the other and are so arranged that the large end of one link and the small end of the successive link are journalled upon the same pin. The .result of this is that instead of both links bearing upon the drum as the chain is wound therearound the edge'of only the large end of the link will bear upon said drum, the small end being maintained out of contact therewith. The rod 35 passes above the pin 23 and spacing sleeve 24. In order to assist in a comparatively frictionless return ofthe wedge to its normal position, a loose sleeve 92 surrounds said spacing sleeve against which the rod 35 rests when the chain 37 becomes slack.

Having now described an illustrative embodiment of the principles of my invention, it is' to be understood that my invention is tion of the jack. This is done not only with not limited to the precise details of construction shown, but that it is entitled to as broadv an interpretation as is permitted by the state of the prior art.

Having described my invention what I claim as new and desire to secure by Letters- Patent, is

l. A lifting jack comprising a main frame including spaced longitudinal members, a

canti-lever extending lengthwise of said frame, load supporting means carried solely by said canti-lever adjacent the free end thereof, the other end of said canti-'lever being pivotally connected to said frame 2. A lifting jack including a main frame,.

a canti-lever pivotally connected to said main frame, a wedge forcible between anI element of said cantilever and an element of said main frame for elevating said cantilever, and means for moving said wedge in a direction to elevate said canti-lever.

3. A lifting jack including a main frame, a canti-lever pivotally connected to said main frame, a load-supporting platform carried by said canti-lever, rollers carried in juxta-position by said canti-lever and said main frame, a wedge forcible between said rollers zfor eleva-ting said canti-lever, and means for moving said Wedge in a direction to elevate said canti-lever. A

4. Alifting jack including a main frame, a. canti-lever pivotally connected to said main frame, a load-supporting platform carried by said canti-lever, rollers mounted in juxtaposition upon said frame and canti-lever,

a wedge forcible between said rollers for elevating said canti-lever, and independent means for eleva-ting said load-supporting platform and for moving said wedge in a direction to raise said canti-lever.

ri lifting jack including' lifting' means. a ratchet wheel operativel` "onneeted to said lifting means, an operating' lever` a lifting' pawl actuated b v said lever and co-acting with the ratchet' wheel. a holding' pawl als-o co-acting with said ratchet wheel. an oscillatablc cani having a portion engaginttgsaid pawl to throw it into or out of operative position. and means on said lever. for oscillatini.y said cani in :in v one of a number of Selective positions ot1 said lever.

ti.' lifting' jacli includinp' lifting means. a ratchet' wheel operatively connected to said liftingr means. an o )eratine' lever. a li'ftino' pawl actuated b v said lever and cit-acting with said ratchet wheel, a holding' pawl also co-acting' with said ratchet. wheel` an oscillatable cam having' a portion engaging; said paw] to throw it into or out of operative position. and means'on said lever for oscillating' said cam in any one of a number of selective positions ot' said lever, said means being' operably connected to said litting' pawl to throw the latter into or out of operative position in certain positions ot said lever. v

7. A lifting' jack including liftingT means, a ratchet. wheel operatively connected to said lifting' means., an operating lever, a lifting pawl actuated by said. lever and co-act ing' with the ratchet wheel, a holding pavvl also cti-acting' with said ratchet wheel, an osoillatable cani having a portion engaging said pawl to throw it into or out of operative position and means for oscillating said cani in any one of a nui'nber of selective positions ot said lever. said means being' operabl)7 connected to said lifting pavvl to throw the latter into and out of operative 'position in certain positions of said lever- S. A lifting' fact; including lifting means.

a ratchet wheel operatively connected to said lift-ing means. an operati-1reT lever, a lifting' pawl actuated by said lever and eo-acting with the ratchet wheel. a holding' pawl also co-acting' with said ratchet Wheel, an oscillatable cam having a portion engaging said pawl to throw the latter into or out of operative position, means movable with said lever 'for oscillating said cam in any one ot a number of selective positions of said lever, said cam being provided with a shoulder engageable with said means when said lever is placed in a certain position for oscillating' said cam to place said holding pawl in operative position.

9. A lifting jack including lifting means, a ratchet wheel operatively connected to said lifting means, an operating lever7 a lifting pawl actuated .hy said lover and (3o-acting esi with the ratchet wheel. a holding pawl also co-actiiu`V with said ratchet wheel. an oscillatablecani having' a portion engaging' said pawl to throw the latter into or out ot' operutive position. means movable with said lever for oscillatingr said cam in any one ot' a nulnhcr of selective positions of said lever. means for automaticallyv raising said lever to a normal position -ot' reposo, said cani being provided with a shoulder engageable. with said movable means when said lever is raised for oscillating said cam to place said holding pawl in operative position and retaining it in that position while said lever is in position ofrepose.

lt). A lifting' jack including lifting meansy a ratchet wheel operatively connected to said lifting' means. an operating lever, a lifting pawl actuated by said lever co-acting with the ratchet wheel` a pi votallv supported holding pawl also co-acting with said ratchet wheel. said holding pawl being provided with keepers on opposite sides of its pivotal axis. an oscillatable am having a tubular portion directed toward said keep ers` an outwardly spring-pressed plunger within said tubular portion. said plunger shifting from. one keeper to the other as the cam is oscillatcd to throw said holdino' pawl into or out ot' ol'ierative position. and means movablewith said lever 'for oscillatiup said cani in any one otl a number of selective positions ol" said level'.

ll. i\ lifting' jack including' lifting means, a ratchet wheel operatively connected to said lifting;l means. an operating' lever` a littvii'ig pawl actuated bv said lever co-actinpr with the ratchet wheel` a pivotaily supported lioldingjT pawl also co-actingy with said ratchet wheel` said holding' pawl being provided with keepers on opposite sides of its pivotal axis. anoscillatablc cam havia;r a tubular portion directed toward said keepers. an outwardly spriiur-prcssed plunger within said tubular extension. said plunger L oscillated to throw said holding pawl into or out of operative position. and means movable with said lever for oscillating said cam in any one of a number of selective positions o't' said lever, said means. being` operatively connected tov said lifting pawl to throw the latter into or out of operative position in certain positions of said lever.

l2. A lifting jack including lifting means, a ratchet wheel operativeljv1 connected to said lifting' means, an operating levery a lit*- ingV pawl actuated by said lever cai-acting with the ratchet wheel, a pivotaily supported holding-pawl also cti-acting with said ratchet wheel, said holding pawl being pro- -vided with keepers on oppositesides of its pivotal axis` an oscillatable cam having a tubular portion directed toward said keepers3 an outwardly spr1ng-pressed plunger within shifting "trom one keeper to the other as the cani said tubular extension, said plunger shifting from one keeper to the other as the cam is oscillated to throwfsaid holding paWl into or out of operative position, and means movable with said lever for oscillating said cam in `any one of a number of selective positions of said lever, said cam being provided with a shoulder engagable With said means when said lever is placed in a certain position, for oscillating said cam to place said holding pawl in operative position.

13. A lifting jack including lifting means, a ratchet wheel operatively connected to said lifting means, an operative lever, a lifting pau'l actuated by said lever co-acting with the. ratchet Wheel, a pivotally supported holding pawl also co-acting with said ratchet Wheel, said holding paWl being provided with .keepers on opposite sides of its pivotal axis, an oscillatable cam having a tubular portion directed toward said keepe1-s, an outwardly spring-pressed plunger Within said tubular extension, said plunger shifting from one keeper to the other as said cam is oscillated to throw said holding pawl into or out of operative position, means movable Within said lever for oscillating sai`` cam in any one of a number of Selective positions of said lever, means for automatically raising said lever to a normal position of repose, said cam being provided with a shoulder engagable with said movable means when said lever is raised for oscillating said cam to place said hclding pawl in operative position and retaining it in that position While said lever is in position of repose.

14. A lifting pawl including lifting means, a ratchet Wheel operatively connected to said lifting means, an operating lever,l a lifting pa'Wl actuated by said lever co-acting with the ratchet Wheel, a pivotally supported holding pawl also co-acting with said ratchet wheel, said holding pawl being provided withf keepers on opposite sides of its pivotal axis, an oscillatable cam having a tubular portion directed toward said keepers, an outwardly spring-pressed plunger Within said tubular extension, said plunger shifting from one keeper to the other a's the cam is oscillated to throw said holding pawl into or out of operative position, said tubular portionbeing formed with a nose contacting with the opposite keeper when the spring-pressed plunger is in-co-action with the keeper holding the pawl in inbperative position, to prevent overturi'iingcf said pawl.I

15. A lifting jack including a lifting means, a ratchet Wheel for operating said lifting means, a holding pawl co-acting' with said ratchet wheel, means for reversing said holding pawltofmove it into and out of operative position/nn operating' lever for said iratchet Wheel, means carried by said lever for actuating said reversing means, a lifting paWl carried by said lever, means for simultaneously bringing said actuating means into engagement with said reversing meansand moving said lifting pawl to its inoperative position, said act'latin means, reversing means and lifting pawl ing so constructed that the re-action of said reversing means, when reversed, is transmitted through said actuating means to cause the return of said lifting pawl to operative position.

y 16. A lifting jack including lifting means, a ratchet Wheel for operating said liftin means, a holding pawl co-actmg With sai ratchet Wheel, means for reversing said pawl to move it into and out of operative position, an operating lever for said ratchet Wheel, means carried by said lever for actuating said eversing means in any one of a number of selective ositions of said lever, a lifting pawl carried) by said lever, means for simultaneously bringing said actuating means into engagement with said reversing means, and moving said lifting pawl into inoperative position, said actuating means, reversing means, and lifting pawl being so constructed that the rel-action of said reversing means, when reversed, is transmitted throughsaidactuating means to cause the return o f said lifting pawl to operative position.

17. A lifting jack comprising a frame, lifting means carried by said frame, a ratchet wheel operatively connected to said lifting means and an-operating lever therefor, a meinber pivotally mounted on said lever, a lifting pawl carried by said member and co-acting With said ratchet Wheel, aholding pawl pivotally mounted on said frame tprovided with keepers on opposite sides o its pivotal axis, pivotally mounted reversing means for said holding pawl including a spring-pressed plunger engageable With either of said keepers when said reversing means is oscillated, said reversing means being formed with recesses defining shoulders, actuting means for said -reversing means including a reciprocable member carried by said pivotally mounted member and engagable with certain of said recesses in selective positions of said lever, a spring connecting said reciprocable member to said pivotally mounted member at one side of the pivotal axis of the latter, means for depressing said reciprocable member to cause it to enter one of said recesses and simultaneously to compress said spring, thereby biasing said pivotally mounted member in a direction to move said lifting pawl to inoperative position, said spring being of less pressure than the resistance of said reversing means to movement When said reciprocable means engages a shoulder thereof yin a direction to oscillate said reversing titl means so as to move said. holding pawl to inoperative position` the pivotally mounted member being thereby biased in a direction4 to throw said lit'ting pawl back into operative position simultaneously with the movement of said holding pawl to inoperative position.

1S. A lifting jack comprising a trame, lifting means carried `by said frame, a ratchet wheel operativelyy connected to said litt-ing means and an operating lever there for, a member pivotally mounted on said lever. a lifting pawl' carried by said member and co-acting with said ratchet wheel, a holding pawl pivotlilly mounted on said frame providedvith keepers on opposite sides ot' its pivotal axis, pivotally mounted reversing means ...for said yholding pawl including a spring-pressed plunger cngageable with either ot said keepers when said reversing means is oscillated, the pressure ot said plunger beingr insuflicient to move said holdingpan'l toVinpperative position until it is relieved vtrpnrthe fnictional resistance ol' the load imp osed uponv it by said ratchet Wheel, througlf'a slight lifting movement of said operating` lever, said reversing means being formed` with' recesses defining shoulders, actuating means for said reversing means including a reciproca'blemember carried by said pivotally mounted member and engagable with certain ot' said recesses in selective positions of said lever, a spring connecting said reciprocable member to said r pivotally mounted member at one side of the t pivotal axis of the latter, means for depressing said 'reciprocable member to cause the same to enter one of said recesses and simultaneously to compress said spring, thereby biasing said pivotally mounted member in a direction to move said'lit'ting pawl to inoperative position, said spring being of less pressure than the resistance to movement orp said reversing means so that when said reciprooable means engages a shoulder of said reversing means to oscillate the latter to cause it to move said holding paivl to inoperative position, the pivotallaY mounted member is thereby biased in a direction to throw said lifting pavvl back into operative position simultaneously with the movement ot' said holdingpavvl to inoperative position.

if). A lifting jack comprising a frame, lifting means carried by said frame, a drum rotatably mounted in said trame, a ratchet wheel tixedirelatively to said drum, Aflexible means windable upon said drum for elevating said lifting means, an operating lever, a member pivotally mounted on said lever, a lifting pawl carried by said member and co-acting with said ratchet Wheel, a holding pawl pivotally carried by said frame and provided with keepers on opposite sides of its pivotal axis, a cam oscillatably mounted co-axially with said ratchet wheel, said cam including a spring-pressed plunger engageable with either of said keepers when said cam is oscillatcd, said cam being formed with recesses defining shoulders, and actuating means t'or said cam including a reciprocable member carried by said pivotally mounted mcmb ,r and engageable with certain ot said recesses in selective positions ot said lever.

20. A lifting jack comprising a trame, lifting means carried by said frame, a drum rotatably mounted in said frame, a ratchet wheel tixcd relative to said drum, flexible means windable upon said drum for elevating said lifting means, an operating lever, a member .pivotally mounted 011 said lever, a lifting paivl carried by said member and co-acting with said ratchet wheel, a holding paw] pivotally carried by said frame and provided with keepers on opposite sides ot its pivotal axis, a cam oscillatably mounted co-axially with said ratchet Wheel, said cam .including a spring-pressed plunger engageable with either of said keepers when said cam is oscillated, said cam being formed with recesses dening shoulders, actuating means for said cam including a rcciprocable member arried by said pivotally mounted member and cngageable with certain of said recesses in selective positions et said lever, a spring connecting said reciprocable member to said pivotally mounted member at one side ot the pivotal axis of the latter, and means l'or depressing said reciprocable mem.- ber to cause the same to enter one of said recesses and simultaneously to compress said spring, thereby biasing said pivotaily mounted member in a direction to move the lifting pawl to inoperative position.

21. A lifting jack including lit'ting means,

a ratchet Wheel operatively connected to said lifting means, an operating lever, a lifting pawl actuated by said lever and co-acting with the ratchet wheel, ay holding pawl alsoco-acting With said ratchet Wheel, an oscillatable cam having a portion engaging said pawl to throw the latter into or out of operative position, and another portion formed with recesses defining shoulders, actuating means for said cam including a reciprocable member carried by said lifting paivl engageable with certain recesses in selective positions of said lever, means for automatically raising said lever to a normal position of repose, said cam being provided with a shoulder engageable With said reciprocable member when said lever is raised, for oscillating said cam to place the holding pawl in operative position and retaining it in that position while said lever is in position ot repose, the engagement of said reeiprocable member with said shoulder moving said lifting palvl to an inoperative position, said lifting pawl and reciprocable member being normally overhalaneed to restore said lifting pawl to operative position by gravity when said reeiprocable member is disengaged from said shoulder by descent of said lever.

A lifting jack including lifting means, a ratchet wheel operatively connected to said lifting means, a holding pawl eO-aoting with said ratchetwheel and means movable with said ratchet wheelfortln'owing said pawl into orout of operative*position with respect to said ratchet wheel atthe respective low and high limits of the range of move ment ot' said lifting means. n

23. A lifting jack including lifting means, a ratchet wheel operatively connected to said lifting means, an operating lever, a lifting pawl actuated by said lever eo-acting with the ratchet wheel, a pivotally supported -holding pa wl also (2o-acting with said ratchet wheel, said pawl being provided with l eepers on opposite. sides of its pivotal axis, an oscillatable cam. having a tubular portion directed toward said keepersan outwardly spring-pressed plunger within said tubular portion, said plunger being adapted to shift from one keeper tothe other as the cam is oscillated to 'throw saidholding pawl into or out ot' operative position. means movable with said rlever for oscillating said cam in any one of a number ol select-ive positions of said 'lever and means onsaid ratchet wheel eugageable with said tubular portion on opposite sides thereolf 'for shitting said pa wl al extreme high and low ranges ot' movement of said lifting means.

24. .k li'lting jack including lifting means. a ratchet wheel Ioperatively eonneeed lo said lifting means. an operating lever, a lifting pawl actuated by said lever eo-aetng with. said ratchet wheel and an auxiliary lifting pawl operable independenlly ot said lever.

A lifting jack including a frame, a

eanti-lever Qivotally connected thereto, a

drum pivotally mounted upon said trame and having a rateln wheel fixedthereto, means tor operating mul ratchet wheel, and a connection between said lifting means it/roos ends or' adjacentv linlis being' jomfnalled upon the same pin, the distance from said pm f i to the lower end ot one ot' said juxtaposed ends being greater than the distance from said pin to the lower edge et' the other, whereby but one ol said ends makes fricI tional engagement with said drum when the ratchet `wheel is operated.

2G. A lifting jack including a 'main frame, independently rotatable vehicle wheels adjacent one end of the frame and a easter adjacent the other` end, said trame inelining downwardly from the end adjacent the caster to the opposite end, a cantilever pivotally connected to said main `frame. at an intermediate point, and means for elevating said cantiwlever. I y

27. ,Ik lifting jack including a main 'trame and a supporting axle theretoi. a canti-lever pivotally Connected to said m'a'in frame, a` platform carriedby said cantilever adjacent said axle and means engaging said eanti-lever and movable rectilinear-y l v 'For elevating said canti-lever.

38. A lifting jack including means, a ratchet wheel operatively nected to said lifting means, a holding pawl eo-acting with said ratchet wheel, and means movable with said ratchet wheel -for throwing aid pawl into or out ot' operative position with respect to said ratchet `wheel, and for stopping the movement of said iiaing vrali-het wheel. at' the respective leitend high limits'o'f the ran'ge ol movement ot' said lifting means.

29. A- lilting jack including lifting means. a. ratchet wheel operatively connei-led to said litting means, and means movable with said ratchet wheel and engageable with another part ot said jack mecha-y my hand.

ERNEST W. HOLMES. 

